VersaPro/ GE Cimplicity - Tracking/ alternating Parts

[TurboCharger]

As a training exercise I am learning to alternate parts while tracking them in VersaPro. I am new to this forum and new to VersaPro.I will be using RFID to share data between stations because I just learned how they work. How could this be accomplish?


Process: There are 2 main conveyors, the enter and exit conveyor. The parts enter 1 of 6 stations. The part is then checked and once completed the part exit that station returning to the exit conveyor.Note that all 6 stations complete the same checking process. I want to alternative the parts between stations from station 1 to 6 or in other words if the next station is busy send the part to the next available station. The enter and exit conveyor will be continuously running. All 6 station will have a turning table(rotating clockwise to enter the station and counter clockwise to exit that station). There will be multiple parts on the enter and exit conveyor so at the same time all 6 stations will be completing the same task and once a station becomes available a new part entering the enter conveyor will move that part to the available station.


Thanks,
Dave

 

[Steve Bailey]

VersaPro is one generation removed from GE's current programming software. The current offering is called Proficy Machine Edition.

What is reading the RFID tags and what options does it have for passing the data from the tags to the PLC? What PLC platform are you using and what modules are you planning to use to interface with the RFID tag reader?

 

[TurboCharger]

I am using GE Fanuc 90-30 PLC. I am using this project to learn more about RFID and how tracking/ alternating between stations can be accomplish using RFID. What module would you recommend due this is only a training excercise to improve my skills in tracking/ alternating between stations. Any help would be appreciated.

 

[Steve Bailey]

Before you can pick a module in the 90-30, you have to know how the RFID reader communicates. I've seen units that send an ASCII string over a serial link, similar to a barcode reader. For that you could use a PCM301 module where you'd have a write a BASIC script to handle the incoming data. If you have a CPU363, it has a serial port that you could set up with ladder logic to read a string of ASCII characters.

I've also seen RFID readers with DeviceNet or Profibus interfaces. The 90-30 has modules for both of those networks.

 

[TurboCharger]

I have a CPU363 and will be using ladder logic to read the string of ASCII characters.

 

[Steve Bailey]

Say hello to the COMMREQ function. Just like getting old, it's not for sissies.

Chapter 9 of GFK-0582 has the information you need to set up your port for serial communications under PLC ladder logic control. You'll need to use one COMMREQ instruction (Code 4300) to set up the port for serial ASCII. Then, depending on the details of the application, you'll need to execute other COMMREQs to manage the data flow from the RFID reader.

The key thing to remember when using the COMMREQ instruction is to trigger it with a one-shot; don't execute one every scan. They may take multiple PLC scans to run to completion, and there are only so many that can be queued up. Read and heed the section headed, "COMMREQ overlap considerations".

 

[RussB]

Say hello to the COMMREQ function. Just like getting old, it's not for sissies.

Chapter 9 of GFK-0582 has the information you need to set up your port for serial communications under PLC ladder logic control. You'll need to use one COMMREQ instruction (Code 4300) to set up the port for serial ASCII. Then, depending on the details of the application, you'll need to execute other COMMREQs to manage the data flow from the RFID reader.

The key thing to remember when using the COMMREQ instruction is to trigger it with a one-shot; don't execute one every scan. They may take multiple PLC scans to run to completion, and there are only so many that can be queued up. Read and heed the section headed, "COMMREQ overlap considerations".

And ALWAYS monitor the Status Register for proper operation and to let you know when your request is completed. The status register should always be set to "0" (zero) just before the COMM_REQ is called with the 1_Shot and monitored to come back with "1" when completed without error or warning. Anything greater than "1" is a potential problem and should be monitored.

 

[TurboCharger]

Thanks I will read up more on the COMMREQ function